Hi,
I've never heard of such an issue. In fact, we've been using Let's encrypt SSL certificate on our own website, which obviously also uses HikaShop for 15 years without problems:
i.imgur.com/0VeqT5O.png
And I'm sure many others do too as Let's encrypt is widely used.
So the problem is probably a server / certificate setup issue and I don't see why HikaShop would be involved.
If you could provide the URL of the website so that we could have a look at the issue (maybe we would need a backend access to temporarily activate HikaShop, while looking at the issue), that would be great. You can do so via our contact form:
www.hikashop.com/support/contact-us.html
Also, please describe in more details how it "does not work".
HIKASHOP ESSENTIAL 60€The basic version. With the main features for a little shop.
HIKAMARKETAdd-on Create a multivendor platform. Enable many vendors on your website.
HIKASERIALAdd-on Sale e-tickets, vouchers, gift certificates, serial numbers and more!
MARKETPLACEPlugins, modules and other kinds of integrations for HikaShop
